name: data-layer-check description: Enforces PropertyIQ data layer architecture rules. Use after modifying frontend data fetching, adding API calls, or changing hooks/fetchers to verify data layer compliance. user-invocable: false

Data Layer Architecture Rules

CRITICAL: ALL frontend data fetching MUST go through @/lib/data.

The Rule

// CORRECT - Use the data layer
import { fetchSnapshotData, useSnapshotData, useDataCard } from "@/lib/data";
 
// WRONG - Never do this outside lib/data/fetchers/
const response = await fetch(`${API_URL}/api/...`);

Available Functions

Function	Purpose
`fetchSnapshotData(metricId, geoLevel, options)`	Current metric values
`fetchTimeSeriesData(metricId, geoLevel, geoId, options)`	Historical data
`fetchScore(geoLevel, geoId)`	PropertyIQ scores
`fetchMarketStats()`	Market statistics

Available Hooks

Hook	Purpose
`useSnapshotData`	Fetch current value with React Query
`useTimeSeriesData`	Fetch time series with React Query
`useDataCard`	Combined snapshot + trend for metric cards
`useDataCardBatch`	Multiple metrics at once

If Endpoint Doesn't Exist

Add fetcher to lib/data/fetchers/
Export from lib/data/index.ts
THEN use in component

Geography ID Formats

Data is keyed by these fields - search must return matching IDs:

Geo Level	Key Field	Example
state	region_name	"California"
metro	cbsa_code	"35620"
county	county_fips	"06001"
zip	postal_code	"90210"

Files to NEVER Import

lib/api/client.ts - Deprecated
Direct fetch() with API_URL outside lib/data